Systems and methods for mixing exhaust gas and reductant

ABSTRACT

A mixing assembly for an exhaust aftertreatment system includes: a mixing body including upstream and downstream mixing body openings, the upstream mixing body opening configured to receive exhaust gas; an upstream plate coupled to the mixing body, the upstream plate including a plurality of upstream plate openings, each of the plurality of upstream plate openings configured to receive a flow percentage that is less than 50% of a total flow of the exhaust gas; a downstream plate coupled to the mixing body downstream from the upstream plate in a direction of exhaust gas flow, the downstream plate including a downstream plate opening; and a swirl plate positioned between the upstream plate and the downstream plate and defining a swirl collection region and a swirl concentration region, the swirl collection region positioned over the plurality of upstream plate openings and the swirl collection region positioned over the downstream plate opening.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/796,016, filed Feb. 20, 2020, which claims priority to IndianProvisional Patent Application No. 201941007211, filed Feb. 25, 2019.The contents of these applications are hereby incorporated by referencein their entireties.

TECHNICAL FIELD

The present application relates generally to systems and methods formixing exhaust gas and reductant in an exhaust aftertreatment system ofan internal combustion engine.

BACKGROUND

For internal combustion engines, such as diesel engines, nitrogen oxide(NO_(x)) compounds may be emitted in exhaust. It may be desirable toreduce NO_(x) emissions to, for example, comply with environmentalregulations. To reduce NO_(x) emissions, a reductant may be dosed intothe exhaust by a dosing system and within an aftertreatment system. Thereductant facilitates conversion of a portion of the exhaust intonon-NO_(x) emissions, such as nitrogen (N₂), carbon dioxide (CO₂), andwater (H₂O), thereby reducing NO_(x) emissions.

In some applications, it may be desirable to facilitate mixing of thereductant in the exhaust. Through this mixing, the reductant may be moreuniformly distributed within the exhaust, thereby enabling more of theexhaust to be converted into non-NO_(x) emissions. Additionally, thismixing may mitigate accumulation of reductant deposits on components ofthe aftertreatment system.

Mixing of reductant and exhaust may be accomplished through the use of avariety of mechanisms. One of these mechanisms is a plate which includesa plurality of openings. The plate is positioned upstream of the doserand the openings are positioned such that the exhaust is caused to swirlas a result of passing through the openings. This swirl enhances mixingof the reductant and the exhaust downstream of the plate. The positionof each opening and an amount of the exhaust that each opening receivesis related to the characteristics of the swirl that is produced by theplate.

SUMMARY

In one embodiment, a mixing assembly for an exhaust aftertreatmentsystem includes a mixing body, an upstream plate, a downstream plate,and a swirl plate. The mixing body includes an upstream mixing bodyopening and a downstream mixing body opening. The upstream mixing bodyopening is configured to receive exhaust gas. The upstream plate iscoupled to the mixing body. The upstream plate includes a plurality ofupstream plate openings. Each of the plurality of upstream plateopenings is configured to receive a flow percentage that is less than50% of a total flow of the exhaust gas. The downstream plate is coupledto the mixing body downstream from the upstream plate in a direction ofexhaust gas flow. The downstream plate includes a downstream plateopening. The swirl plate is positioned between the upstream plate andthe downstream plate and defines a swirl collection region and a swirlconcentration region that is contiguous with the swirl collectionregion. The swirl collection region is positioned over the plurality ofupstream plate openings and the swirl collection region is positionedover the downstream plate opening.

In another embodiment, a mixing assembly includes a mixing body, anupstream plate, and an injector mount. The mixing body includes anupstream mixing body opening and a downstream mixing body opening. Theupstream mixing body opening is configured to receive exhaust gas. Theupstream plate is coupled to the mixing body. The upstream plateincludes a first upstream plate opening a second upstream plate opening.The first upstream plate opening is configured to receive a first flowpercentage that is between 20% and 40%, inclusive of a total flow of theexhaust gas. The second upstream plate opening is configured to receivea second flow percentage that is between 20% and 40% inclusive of thetotal flow of the exhaust gas. The injector mount is coupled to themixing body and configured to be coupled to an injector. The injectormount is defined by an injector center axis that extends between thefirst upstream plate opening and the second upstream plate opening.

In yet another embodiment, a mixing assembly includes a mixing body, anupstream plate, and a swirl plate. The mixing body includes an upstreammixing body opening and a downstream mixing body opening. The upstreammixing body opening is configured to receive exhaust gas. The upstreamplate is coupled to the mixing body. The upstream plate includes a firstupstream plate opening and a second upstream plate opening. The firstupstream plate opening is configured to receive a first flow percentagethat is between 20% and 40%, inclusive of a total flow of the exhaustgas. The second upstream plate opening is configured to receive a secondflow percentage that is between 20% and 40% inclusive of the total flowof the exhaust gas. The swirl plate is coupled to the upstream plate anddefines a swirl collection region and a swirl concentration region thatis contiguous with the swirl collection region. The swirl collectionregion extends across the first upstream plate opening and the secondupstream plate opening. The swirl collection region is separated fromthe first upstream plate opening and second upstream plate opening bythe swirl plate.

BRIEF DESCRIPTION OF THE DRAWINGS

The details of one or more implementations are set forth in theaccompanying drawings and the description below. Other features,aspects, and advantages of the disclosure will become apparent from thedescription, the drawings, and the claims, in which:

FIG. 1 is a block schematic diagram of an example exhaust aftertreatmentsystem;

FIG. 2 is a perspective view of a mixing assembly for an exhaustaftertreatment system;

FIG. 3 is a front side view of the mixing assembly shown in FIG. 2 froman upstream side looking downstream;

FIG. 4 is a perspective view of the mixing assembly shown in FIG. 2 withcertain components omitted to allow for viewing of certain othercomponents;

FIG. 5 is another perspective view of the mixing assembly shown in FIG.2 with certain components omitted;

FIG. 6 is a rear side view of the mixing assembly shown in FIG. 2 from adownstream side looking upstream with certain components omitted;

FIG. 7 is a rear side view of the mixing assembly shown in FIG. 2 from adownstream side looking upstream;

FIGS. 8-10 are images of velocity magnitudes within the mixing assemblyshown in FIG. 2; and

FIGS. 11 and 12 are images of temperature gradient within the mixingassembly shown in FIG. 2.

It will be recognized that some or all of the figures are schematicrepresentations for purposes of illustration. The figures are providedfor the purpose of illustrating one or more implementations with theexplicit understanding that they will not be used to limit the scope orthe meaning of the claims.

DETAILED DESCRIPTION

Following below are more detailed descriptions of various conceptsrelated to, and implementations of, methods, apparatuses, and systemsfor mixing exhaust gas and reductant in an exhaust aftertreatment systemof an internal combustion engine. The various concepts introduced aboveand discussed in greater detail below may be implemented in any ofnumerous ways, as the described concepts are not limited to anyparticular manner of implementation. Examples of specificimplementations and applications are provided primarily for illustrativepurposes.

I. Overview

Internal combustion engines (e.g., diesel internal combustion engines,etc.) produce exhaust gas that is often treated by a dosing modulewithin an exhaust aftertreatment system. A dosing module typicallytreats exhaust gas using a reductant. The reductant is adsorbed by acatalyst. The adsorbed reductant in the catalyst functions to reduceNO_(x) in the exhaust gas.

In order to effectively treat the exhaust gas using the reductant, thereductant must be dispersed within the exhaust gas. Additionally, if thereductant is not dispersed within the exhaust gas, deposits of thereductant may form. These deposits may accumulate over time and requirethat the exhaust aftertreatment system be cleaned or serviced. Cleaningof the exhaust aftertreatment system can sometimes be accomplishedthrough a regeneration cycle where the temperature of the exhaust gas isincreased. However, such regeneration cycles increase fuel consumptionand are undesirable.

In order to decrease the accumulation of deposits, some systems utilizemixing devices. However, these mixing devices typically increase theback pressure of the system. Increasing back pressure in the exhaustaftertreatment system causes the exhaust aftertreatment system tooperate inefficiently and is undesirable. Thus, these systems are facedwith a tradeoff between deposit accumulation and increases inbackpressure. To account for this tradeoff, some systems limit the rateat which the reductant can be used to treat the gas, emit higher levelsof NOR, and/or perform frequent regeneration cycles.

Implementations described herein are related to a mixing assembly thatensures effective distribution of the reductant within the exhaust gasand mitigates the formation and accumulation of reductant deposits.Implementations described herein utilize an upstream plate having aplurality of openings, none of which receives (e.g., transmits, permitsto pass, etc.) more than 60% of a total flow of the exhaust gas, adownstream plate having a single opening, a swirl plate that creates aswirl collection region and a swirl concentration region, and two splashplates that are positioned underneath the injector and aid in minimizingimpingement of the reductant on various surfaces within the mixingassembly. The plurality of openings in the upstream plate are arrangedto create shear flows and provide relatively high temperature exhaustgas to areas where reductant deposits may otherwise accumulate.

Through these features, implementations described herein are capable ofeffectively dispersing the reductant in the exhaust gas and mitigatingthe accumulation of reductant deposits. As a result, implementationsdescribed herein require less cleaning, result in less warranty claims,and enable decreased fuel consumption compared to other systems.Additionally, the implementations described herein may have a smallerspace claim than other systems. Additionally, implementations hereinprovide for a smaller pressure drop than other systems due to thearrangement of the openings on the upstream plate, the swirl plate, thesplash plates, and the opening in the downstream plate.

II. Overview of Exhaust Aftertreatment System

FIG. 1 depicts an exhaust aftertreatment system 100 having an examplereductant delivery system 102 for an exhaust conduit system 104. Theexhaust aftertreatment system 100 includes the reductant delivery system102, a particulate filter (e.g., a diesel particulate filter (DPF)) 106,a decomposition chamber 108 (e.g., reactor, reactor pipe, etc.), and aSCR catalyst 110.

The DPF 106 is configured to (e.g., structured to, able to, etc.) removeparticulate matter, such as soot, from exhaust gas flowing in theexhaust conduit system 104. The DPF 106 includes an inlet, where theexhaust gas is received, and an outlet, where the exhaust gas exitsafter having particulate matter substantially filtered from the exhaustgas and/or converting the particulate matter into carbon dioxide. Insome implementations, the DPF 106 may be omitted.

The decomposition chamber 108 is configured to convert a reductant intoammonia. The reductant may be, for example, urea, diesel exhaust fluid(DEF), Adblue®, a urea water solution (UWS), an aqueous urea solution(e.g., AUS32, etc.), and other similar fluids. The decomposition chamber108 includes an inlet in fluid communication with the DPF 106 to receivethe exhaust gas containing NO_(x) emissions and an outlet for theexhaust gas, NO_(x) emissions, ammonia, and/or reductant to flow to theSCR catalyst 110.

The decomposition chamber 108 includes the reductant delivery system102. The reductant delivery system 102 includes a dosing module 112(e.g., doser, etc.) configured to dose the reductant into thedecomposition chamber 108 (e.g., via an injector). The dosing module 112is mounted to the decomposition chamber 108 such that the dosing module112 may dose the reductant into the exhaust gas flowing in the exhaustconduit system 104. The dosing module 112 may include an insulatorinterposed between a portion of the dosing module 112 and the portion ofthe decomposition chamber 108 on which the dosing module 112 is mounted.

The dosing module 112 is fluidly coupled to (e.g., fluidly configured tocommunicate with, etc.) a reductant source 114. The reductant source 114may include multiple reductant sources 114. The reductant source 114 maybe, for example, a diesel exhaust fluid tank containing Adblue®. Areductant pump 116 (e.g., supply unit, etc.) is used to pressurize thereductant from the reductant source 114 for delivery to the dosingmodule 112. In some embodiments, the reductant pump 116 is pressurecontrolled (e.g., controlled to obtain a target pressure, etc.). Thereductant pump 116 includes a reductant filter 118. The reductant filter118 filters (e.g., strains, etc.) the reductant prior to the reductantbeing provided to internal components (e.g., pistons, vanes, etc.) ofthe reductant pump 116. For example, the reductant filter 118 mayinhibit or prevent the transmission of solids (e.g., solidifiedreductant, contaminants, etc.) to the internal components of thereductant pump 116. In this way, the reductant filter 118 may facilitateprolonged desirable operation of the reductant pump 116. In someembodiments, the reductant pump 116 is coupled to a chassis of a vehicleassociated with the exhaust aftertreatment system 100.

The dosing module 112 includes at least one injector 120. Each injector120 is configured to dose the reductant into the exhaust gas (e.g.,within the decomposition chamber 108, etc.). In some embodiments, thereductant delivery system 102 also includes an air pump 122. In theseembodiments, the air pump 122 draws air from an air source 124 (e.g.,air intake, etc.) and through an air filter 126 disposed upstream of theair pump 122. Additionally, the air pump 122 provides the air to thedosing module 112 via a conduit. In these embodiments, the dosing module112 is configured to mix the air and the reductant into an air-reductantmixture and to provide the air-reductant mixture into the decompositionchamber 108. In other embodiments, the reductant delivery system 102does not include the air pump 122 or the air source 124. In suchembodiments, the dosing module 112 is not configured to mix thereductant with air.

The dosing module 112 and the reductant pump 116 are also electricallyor communicatively coupled to a reductant delivery system controller128. The reductant delivery system controller 128 is configured tocontrol the dosing module 112 to dose the reductant into thedecomposition chamber 108. The reductant delivery system controller 128may also be configured to control the reductant pump 116.

The reductant delivery system controller 128 includes a processingcircuit 130. The processing circuit 130 includes a processor 132 and amemory 134. The processor 132 may include a microprocessor, anapplication-specific integrated circuit (ASIC), a field-programmablegate array (FPGA), etc., or combinations thereof. The memory 134 mayinclude, but is not limited to, electronic, optical, magnetic, or anyother storage or transmission device capable of providing a processor,ASIC, FPGA, etc. with program instructions. This memory 134 may includea memory chip, Electrically Erasable Programmable Read-Only Memory(EEPROM), Erasable Programmable Read Only Memory (EPROM), flash memory,or any other suitable memory from which the reductant delivery systemcontroller 128 can read instructions. The instructions may include codefrom any suitable programming language. The memory 134 may includevarious modules that include instructions which are configured to beimplemented by the processor 132.

The reductant delivery system controller 128 is configured tocommunicate with a central controller 136 (e.g., engine control unit(ECU), engine control module (ECM), etc.) of an internal combustionengine having the exhaust aftertreatment system 100. In someembodiments, the central controller 136 and the reductant deliverysystem controller 128 are integrated into a single controller.

In some embodiments, the central controller 136 is communicable with adisplay device (e.g., screen, monitor, touch screen, heads up display(HUD), indicator light, etc.). The display device may be configured tochange state in response to receiving information from the centralcontroller 136. For example, the display device may be configured tochange between a static state (e.g., displaying a green light,displaying a “SYSTEM OK” message, etc.) and an alarm state (e.g.,displaying a blinking red light, displaying a “SERVICE NEEDED” message,etc.). based on a communication from the central controller 136. Bychanging state, the display device may provide an indication to a user(e.g., operator, etc.) of a status (e.g., operation, in need of service,etc.) of the reductant delivery system 102.

The decomposition chamber 108 is located upstream of the SCR catalyst110. As a result, the reductant is injected upstream of the SCR catalyst110 such that the SCR catalyst 110 receives a mixture of the reductantand exhaust gas. The reductant droplets undergo the processes ofevaporation, thermolysis, and hydrolysis to form non-NO_(x) emissions(e.g., gaseous ammonia, etc.) within the exhaust conduit system 104.

The SCR catalyst 110 is configured to assist in the reduction of NO_(x)emissions by accelerating a NO_(x) reduction process between the ammoniaand the NO_(x) of the exhaust gas into diatomic nitrogen, water, and/orcarbon dioxide. The SCR catalyst 110 includes an inlet in fluidcommunication with the decomposition chamber 108 from which exhaust gasand reductant are received and an outlet in fluid communication with anend of the exhaust conduit system 104.

The exhaust aftertreatment system 100 may further include an oxidationcatalyst (e.g., a diesel oxidation catalyst (DOC)) in fluidcommunication with the exhaust conduit system 104 (e.g., downstream ofthe SCR catalyst 110 or upstream of the DPF 106) to oxidize hydrocarbonsand carbon monoxide in the exhaust gas.

In some implementations, the DPF 106 may be positioned downstream of thedecomposition chamber 108. For instance, the DPF 106 and the SCRcatalyst 110 may be combined into a single unit. In someimplementations, the dosing module 112 may instead be positioneddownstream of a turbocharger or upstream of a turbocharger.

The exhaust aftertreatment system 100 also includes a mixing assembly138 (e.g., mixer, multi-stage mixer, etc.). The mixing assembly 138 isdisposed between a decomposition chamber upstream portion 140 and adecomposition chamber downstream portion 142. Together, thedecomposition chamber upstream portion 140, the mixing assembly 138, andthe decomposition chamber downstream portion 142, form the mixingassembly 138. The dosing module 112 is coupled to the mixing assembly138 and the injector 120 is configured to dose the reductant into themixing assembly 138. As will be explained in more detail herein, themixing assembly 138 functions to mix the exhaust gas received from thedecomposition chamber upstream portion 140 with the reductant providedby the mixing assembly 138 and provide the decomposition chamberdownstream portion 142 with exhaust gas that have been mixed with thereductant.

III. Example Mixing Assembly

FIGS. 2-12 illustrate the mixing assembly 138 in greater detail. Themixing assembly 138 includes a mixing body 200 (e.g., frame, structure,etc.). The mixing body 200 has a mixing body center axis C_(body). Themixing body 200 is generally cylindrical and has a mixing body diameterD_(mb) that is less than the mixing body upstream coupler diameterD_(mbuc). In various embodiments, the mixing body diameter D_(mb) isbetween 200 millimeters (mm) and 220 mm, inclusive. In some embodiments,the mixing body diameter D_(mb) is approximately equal to 210.9 mm.

The mixing assembly 138 also includes a mixing body upstream coupler 202(e.g., joint, flange, channel, etc.). The mixing body 200 is contiguouswith the mixing body upstream coupler 202. In various embodiments, themixing body upstream coupler 202 is welded, fastened, or otherwisecoupled to the mixing body 200. The mixing body upstream coupler 202 isconfigured to be (e.g., structured to be, capable of being, etc.)positioned adjacent to the decomposition chamber upstream portion 140.In some embodiments, the mixing body upstream coupler 202 is coupled tothe decomposition chamber upstream portion 140. The mixing body upstreamcoupler 202 is generally cylindrical and has a mixing body upstreamcoupler diameter D_(mbuc). In various embodiments, the mixing bodyupstream coupler diameter D_(mbuc) is between 220 mm and 250 mm,inclusive. In some embodiments, the mixing body upstream couplerdiameter D_(mbuc) is approximately equal to 239.2 mm.

The mixing assembly 138 also includes a mixing body downstream coupler206 (e.g., joint, flange, etc.). The mixing body downstream coupler 206is configured to positioned adjacent to the decomposition chamberdownstream portion 142. In some embodiments, the mixing body downstreamcoupler 206 is coupled to the decomposition chamber downstream portion142. The mixing body downstream coupler 206 is contiguous with themixing body 200. In various embodiments, the mixing body downstreamcoupler 206 is structurally integrated with (e.g., formed from the samematerial as, etc.) the mixing body 200. The mixing body downstreamcoupler 206 is generally cylindrical and has a mixing body downstreamcoupler diameter D_(mbdc) that is greater than the mixing body diameterD_(mbc). In various embodiments, the mixing body downstream couplerdiameter D_(mbdc) is approximately (e.g., is within 5% of, is within 2%of, etc.) equal to the mixing body upstream coupler diameter D_(mbuc).In various embodiments, the mixing body downstream coupler diameterD_(mbdc) is between 220 mm and 250 mm, inclusive. In some embodiments,the mixing body downstream coupler diameter D_(mbdc) is approximatelyequal to 238.2 mm.

The mixing body upstream coupler 202 has a mixing body upstream couplerplane P_(upstream). The mixing body upstream coupler plane P_(upstream)is coincident with an outermost edge of the mixing body upstream coupler202. The mixing body center axis C_(body) is orthogonal to the mixingbody upstream coupler plane P_(upstream) and extends through the mixingbody upstream coupler plane P_(upstream).

The mixing body downstream coupler 206 has a mixing body downstreamcoupler plane P_(downstream). The mixing body downstream coupler planeP_(downstream) is coincident with an outermost edge of the mixing bodydownstream coupler 206. The mixing body center axis C_(body) isorthogonal to the mixing body downstream coupler plane P_(downstream)and extends through the mixing body downstream coupler planeP_(downstream).

The mixing body upstream coupler plane P_(upstream) is parallel to themixing body downstream coupler plane P_(downstream). The mixing bodyupstream coupler plane P_(upstream) is separated from the mixing bodydownstream coupler plane P_(downstream) by a mixing body length L_(body)(e.g., as measured along an axis parallel to the mixing body center axisC_(body)). In various embodiments, the mixing body length L_(body) isbetween 120 mm and 145 mm, inclusive. In some embodiments, the mixingbody length L_(body) is approximately equal to 134.8 mm.

The mixing assembly 138 also includes an injector mount 208. Theinjector mount 208 is coupled to the mixing body 200. For example, theinjector mount 208 may be welded or fastened to the mixing body 200. Theinjector mount 208 is configured to couple the injector 120 to themixing body 200. The injector 120 has an injector center axisC_(injector). As will be explained in more detail herein, the injector120 is configured to dose the reductant into the mixing body 200 alongthe injector center axis C_(injector).

The injector mount 208 is also defined by an injector plane P_(injector)along which the injector center axis C_(injector) is disposed when theinjector 120 is coupled to the mixing body 200 via the injector mount208. In various embodiments, the injector plane P_(injector) is parallelto the mixing body upstream coupler plane P_(upstream) and the mixingbody downstream coupler plane P_(downstream).

The injector mount 208 is further defined by an first injector angleα_(injector) and a second injector angle β_(injector). The firstinjector angle α_(injector) is measured between the injector center axisC_(injector) and a first reference axis G₁ that is disposed along theinjector plane P_(injector) and orthogonal to the mixing body centeraxis C_(body). In various embodiments, the first injector angleα_(injector) is between 90° and 110°, inclusive. In some embodiments,the first reference axis G₁ is substantially horizontal (e.g., within 5%of a horizontal axis, parallel to the horizontal axis, etc.). The secondinjector angle β_(injector) is measured between the injector center axisC_(injector) and a second reference axis G₂ that extends through theinjector plane P_(injector) and is parallel to the mixing body centeraxis C_(body). In various embodiments, the second injector angleβ_(injector) is between 80° and 110°, inclusive. In some embodiments,the second injector angle β_(injector) is 90°.

The injector plane P_(injector) is separated from the mixing bodyupstream coupler plane P_(upstream) by an injector length L_(injector).The injector length L_(injector) is measured along a direction parallelto the mixing body center axis C_(body). In some embodiments, theinjector length L_(injector) is between 30% and 60%, inclusive (e.g.,30%, 35%, 40%, 45%, 50%, 55%, 60%, etc.) of the mixing body lengthL_(body). In one embodiment, the injector length L_(injector) is 35% ofthe mixing body length L_(body). In embodiments where the secondinjector angle β_(injector) is not 90°, the injector length L_(injector)is the maximum distance separating the injector plane P_(injector) fromthe mixing body upstream coupler plane P_(upstream) within the mixingbody 200. In various embodiments, the injector length L_(injector) isbetween 35 mm and 55 mm, inclusive. In some embodiments, the injectorlength L_(injector) is approximately equal to 47.2 mm.

FIG. 3 illustrates the mixing assembly 138 looking from the mixing bodyupstream coupler 202 and towards the mixing body downstream coupler 206(which is not shown in FIG. 3). The injector center axis C_(injector) isseparated from the mixing body center axis C_(body) by an injectoroffset O_(injector). The injector offset O_(injector) is measured alongan axis that is orthogonal to and coincident with the mixing body centeraxis C_(body). In some embodiments, the injector offset O_(injector) isbetween 15% and 30%, inclusive (e.g., 15%, 20%, 25%, 30%, 35%, etc.) ofthe mixing body diameter D_(mb). In some embodiments, the injectoroffset O_(injector) is approximately 23% of the mixing body diameterD_(mb). In various embodiments, the injector offset O_(injector) isbetween 35 mm and 60 mm, inclusive. In some embodiments, the injectoroffset O_(injector) is approximately equal to 48.6 mm.

The injector mount 208 may be configured such that the first injectorangle α_(injector), the second injector angle β_(injector), the injectorlength L_(injector), or the injector offset O_(injector) have targetvalues such that the mixing assembly 138 is tailored for a targetapplication. In some embodiments, the first injector angle α_(injector),the second injector angle β_(injector), the injector lengthL_(injector), or the injector offset O_(injector) are selected based onthe injector 120. In other embodiments, the injector 120 is selectedbased on any of the first injector angle α_(injector), the secondinjector angle β_(injector), the injector length L_(injector), or theinjector offset O_(injector).

The mixing assembly 138 also includes an upstream plate 300. Theupstream plate 300 is coupled to the mixing body 200 across or within anupstream mixing body opening 301 of the mixing body 200. The upstreamplate 300 includes an upstream plate edge 302 that is coupled to themixing body 200 relative to the injector axis C_(injector). For example,the upstream plate edge 302 may include an alignment feature (e.g., tab,recess, etc.) that is received within an alignment feature in the mixingbody 200 when the upstream plate edge 302 is coupled to the mixing body200 and the alignment features may be positioned based upon the injectoraxis C_(injector). In various embodiments, the upstream plate edge 302is welded or fastened to the mixing body 200. The upstream plate 300separates a portion (e.g., a downstream portion, etc.) of the mixingbody 200 from the decomposition chamber upstream portion 140 such thatexhaust gas flowing into the mixing body 200 must first pass throughupstream plate 300.

The upstream plate 300 is shown and described herein with relation to anexample embodiment. It is understood that the configuration of theupstream plate 300 may be different for various applications. Forexample, the configuration of the upstream plate 300 may change basedupon the arrangement of the injector center axis C_(injector).

The upstream plate 300 includes a first upstream plate opening 304. Thefirst upstream plate opening 304 provides a pathway for the exhaust gasto pass through the upstream plate 300. The first upstream plate opening304 has a first upstream plate opening area A₁ which is thecross-sectional area through which the exhaust gas passes through theupstream plate 300 at a first flow rate percentage (e.g., mass flow ratepercentage, volumetric flow rate percentage, etc.) F₁ via the firstupstream plate opening 304. The first upstream plate opening 304 is notcontiguous with the upstream plate edge 302. In this way, the firstupstream plate opening 304 is entirely bordered by (e.g., is placedwithin, etc.) the upstream plate 300.

The upstream plate 300 includes a second upstream plate opening 306. Thesecond upstream plate opening 306 provides another pathway for theexhaust gas to pass through the upstream plate 300. The second upstreamplate opening 306 has a second upstream plate opening area A₂ which isthe cross-sectional area through which the exhaust gas passes throughthe upstream plate 300 at a second flow rate percentage F₂ via thesecond upstream plate opening 306. In an example embodiment, the secondupstream plate opening area A₂ is greater than the first upstream plateopening area A₁ and the second flow rate percentage F₂ is less than thefirst flow rate percentage F₁. Unlike the first upstream plate opening304, the second upstream plate opening 306 is contiguous with theupstream plate edge 302. In this way, the second upstream plate opening306 is bordered by the upstream plate 300 and the mixing body 200.

The upstream plate 300 includes a third upstream plate opening 308. Thethird upstream plate opening 308 provides yet another pathway for theexhaust gas to pass through the upstream plate 300. The third upstreamplate opening 308 has a third upstream plate opening area A₃ which isthe cross-sectional area through which the exhaust gas passes throughthe upstream plate 300 at a third flow rate percentage F₃ via the thirdupstream plate opening 308. In the example embodiment, the thirdupstream plate opening area A₃ is less than the second upstream plateopening area A₂ and the third flow rate percentage F₃ is less than thesecond flow rate percentage F₂. The third upstream plate opening 308 isnot contiguous with the upstream plate edge 302. In this way, the thirdupstream plate opening 308 is entirely bordered by the upstream plate300.

The upstream plate 300 includes a fourth upstream plate opening 310. Thefourth upstream plate opening 310 provides yet another pathway for theexhaust gas to pass through the upstream plate 300. The fourth upstreamplate opening 310 has a fourth upstream plate opening area A₄ which isthe cross-sectional area through which the exhaust gas passes throughthe upstream plate 300 at a fourth flow rate percentage F₄ via thefourth upstream plate opening 310. In the example embodiment, the fourthupstream plate opening area A₄ is less than the third upstream plateopening area A₃ and the fourth flow rate percentage F₄ is less than thethird flow rate percentage F₃. The fourth upstream plate opening 310 isnot contiguous with the upstream plate edge 302. In this way, the fourthupstream plate opening 310 is entirely bordered by the upstream plate300.

The upstream plate 300 includes a fifth upstream plate opening 312. Thefifth upstream plate opening 312 provides yet another pathway for theexhaust gas to pass through the upstream plate 300. The fifth upstreamplate opening 312 has a fifth upstream plate opening area A₅ which isthe cross-sectional area through which the exhaust gas passes throughthe upstream plate 300 at a fifth flow rate percentage F₅ via the fifthupstream plate opening 312. In the example embodiment, the fifthupstream plate opening area A₅ is less than the fourth upstream plateopening area A₄ and the fifth flow rate percentage F₅ is less than thefourth flow rate percentage F₄. The fifth upstream plate opening 312 isnot contiguous with the upstream plate edge 302. In this way, the fifthupstream plate opening 312 is entirely bordered by the upstream plate300. Unlike the first upstream plate opening 304, the second upstreamplate opening 306, the third upstream plate opening 308, and the fourthupstream plate opening 310, the fifth upstream plate opening 312 issubstantially circular.

The upstream plate 300 includes a sixth upstream plate opening 314. Thesixth upstream plate opening 314 provides yet another pathway for theexhaust gas to pass through the upstream plate 300. The sixth upstreamplate opening 314 has a sixth upstream plate opening area A₆ which isthe cross-sectional area through which the exhaust gas passes throughthe upstream plate 300 at a sixth flow rate percentage F₆ via the sixthupstream plate opening 314. In the example embodiment, the sixthupstream plate opening area A₆ is approximately equal to the fifthupstream plate opening area A₅ and the sixth flow rate percentage F₆ isless than the fourth flow rate percentage F₄ and greater than the fifthflow rate percentage F₅. The sixth upstream plate opening 314 is notcontiguous with the upstream plate edge 302. In this way, the sixthupstream plate opening 314 is entirely bordered by the upstream plate300. Like the fifth upstream plate opening 312, the sixth upstream plateopening 314 is substantially circular.

The upstream plate 300 includes a seventh upstream plate opening 316.The seventh upstream plate opening 316 provides yet another pathway forthe exhaust gas to pass through the upstream plate 300. The seventhupstream plate opening 316 has a seventh upstream plate opening area A₇which is the cross-sectional area through which the exhaust gas passesthrough the upstream plate 300 at a seventh flow rate percentage F₇ viathe seventh upstream plate opening 316. In the example embodiment, theseventh upstream plate opening area A₇ is approximately equal to thefifth upstream plate opening area A₅ and the seventh flow ratepercentage F₇ is less than the sixth flow rate percentage F₆ and greaterthan the fifth flow rate percentage F₈. The seventh upstream plateopening 316 is not contiguous with the upstream plate edge 302. In thisway, the seventh upstream plate opening 316 is entirely bordered by theupstream plate 300. Like the fifth upstream plate opening 312, theseventh upstream plate opening 316 is substantially circular.

The upstream plate 300 includes an eighth upstream plate opening 318.The eighth upstream plate opening 318 provides yet another pathway forthe exhaust gas to pass through the upstream plate 300. The eighthupstream plate opening 318 has an eighth upstream plate opening area A₈which is the cross-sectional area through which the exhaust gas passesthrough the upstream plate 300 at an eighth flow rate percentage F₈ viathe eighth upstream plate opening 318. In the example embodiment, theeighth upstream plate opening area A₈ is less than the fifth upstreamplate opening area A₅ and the eighth flow rate percentage F₈ is lessthan the fifth flow rate percentage F₅. Like the second upstream plateopening 306, the eighth upstream plate opening 318 is contiguous withthe upstream plate edge 302. In this way, the eighth upstream plateopening 318 is bordered by the upstream plate 300 and the mixing body200. The eighth upstream plate opening 318 is substantiallysemi-circular.

The upstream plate 300 includes a ninth upstream plate opening 320. Theninth upstream plate opening 320 provides yet another pathway for theexhaust gas to pass through the upstream plate 300. The ninth upstreamplate opening 320 has a ninth upstream plate opening area A₉ which isthe cross-sectional area through which the exhaust gas passes throughthe upstream plate 300 at a ninth flow rate percentage F₉ via the ninthupstream plate opening 320. In the example embodiment, the ninthupstream plate opening area A₉ is approximately equal to the eighthupstream plate opening area A₈ and the ninth flow rate percentage F₉ isgreater than the eighth flow rate percentage F₈ and less than the fifthflow rate percentage F₅. Like the second upstream plate opening 306, theninth upstream plate opening 320 is contiguous with the upstream plateedge 302. In this way, the ninth upstream plate opening 320 is borderedby the upstream plate 300 and the mixing body 200. Like the eighthupstream plate opening 318, the ninth upstream plate opening 320 issubstantially semi-circular.

The upstream plate 300 includes a tenth upstream plate opening 322. Thetenth upstream plate opening 322 provides yet another pathway for theexhaust gas to pass through the upstream plate 300. The tenth upstreamplate opening 322 has a tenth upstream plate opening area A₁₀ which isthe cross-sectional area through which the exhaust gas passes throughthe upstream plate 300 at a tenth flow rate percentage F₁₀ via the tenthupstream plate opening 322. In the example embodiment, the tenthupstream plate opening area A₁₀ is approximately equal to the eighthupstream plate opening area A₈ and the tenth flow rate percentage F₁₀ isapproximately equal to the ninth flow rate percentage F₉. Like thesecond upstream plate opening 306, the tenth upstream plate opening 322is contiguous with the upstream plate edge 302. In this way, the tenthupstream plate opening 322 is bordered by the upstream plate 300 and themixing body 200. Like the eighth upstream plate opening 318, the tenthupstream plate opening 322 is substantially semi-circular.

The upstream plate 300 includes an eleventh upstream plate opening 324.The eleventh upstream plate opening 324 provides yet another pathway forthe exhaust gas to pass through the upstream plate 300. The eleventhupstream plate opening 324 has an eleventh upstream plate opening areaA₁₁ which is the cross-sectional area through which the exhaust gaspasses through the upstream plate 300 at an eleventh flow ratepercentage F₁₁ via the eleventh upstream plate opening 324. In theexample embodiment, the eleventh upstream plate opening area A₁₁ isapproximately equal to the eighth upstream plate opening area A₈ and theeleventh flow rate percentage F₁₁ is approximately equal to the ninthflow rate percentage F₉. Like the second upstream plate opening 306, theeleventh upstream plate opening 324 is contiguous with the upstreamplate edge 302. In this way, the eleventh upstream plate opening 324 isbordered by the upstream plate 300 and the mixing body 200. Like theeighth upstream plate opening 318, the eleventh upstream plate opening324 is substantially semi-circular.

In summary, the upstream plate 300 is configured such that

A ₁₁ ≅A ₁₀ ≅A ₉ ≅A ₈ <A ₇ ≅A ₆ =A ₅ <A ₄ <A ₃ <A ₁ <A ₂  (1)

F ₈ <F ₁₁ ≅F ₁₀ ≅F ₉ <F ₅ <F ₇ <F ₆ <F ₄ <F ₃ <F ₂ <F ₁  (2)

100%=F ₁ +F ₂ +F ₃ +F ₄ +F ₅ +F ₆ +F ₇ +F ₈ +F ₉ +F ₁₀ +F ₁₁  (3)

in the example embodiment. Table 1 illustrates a configuration of theupstream plate 300 according to the example embodiment.

TABLE 1 Flow Rate Percentages of the Total Flow of the Exhaust GasThrough the Upstream Plate 300 in the Example Embodiment. F1  32.6967%F2  29.9112% F3   6.7403% F4   6.5756% F5    3.053% F6   3.5001% F7  3.2217% F8  1.98608% F9   2.3371% F10   2.359% F11    2.35%

In other applications, the upstream plate 300 has other similarconfigurations so that the upstream plate 300 can be tailored for atarget application. However, the upstream plate 300 is always configuredsuch that none of the first flow rate percentage F₁, the second flowrate percentage F₂, the third flow rate percentage F₃, the fourth flowrate percentage F₄, the fifth flow rate percentage F₅, the sixth flowrate percentage F₆, the seventh flow rate percentage F₇, the eighth flowrate percentage F₈, the ninth flow rate percentage F₉, the tenth flowrate percentage F₁₀, or the eleventh flow rate percentage F₁₁ are equalto or exceed 60% of the total flow of the exhaust gas. For example, insome embodiments, none of the first flow rate percentage F₁, the secondflow rate percentage F₂, the third flow rate percentage F₃, the fourthflow rate percentage F₄, the fifth flow rate percentage F₅, the sixthflow rate percentage F₆, the seventh flow rate percentage F₇, the eighthflow rate percentage F₈, the ninth flow rate percentage F₉, the tenthflow rate percentage F₁₀, or the eleventh flow rate percentage F₁₁ areequal to or exceed 50% of the total flow of the exhaust gas. In otherembodiments, none of the first flow rate percentage F₁, the second flowrate percentage F₂, the third flow rate percentage F₃, the fourth flowrate percentage F₄, the fifth flow rate percentage F₅, the sixth flowrate percentage F₆, the seventh flow rate percentage F₇, the eighth flowrate percentage F₈, the ninth flow rate percentage F₉, the tenth flowrate percentage F₁₀, or the eleventh flow rate percentage F₁₁ are equalto or exceed 45% of the total flow of the exhaust gas. In still otherembodiments, none of the first flow rate percentage F₁, the second flowrate percentage F₂, the third flow rate percentage F₃, the fourth flowrate percentage F₄, the fifth flow rate percentage F₅, the sixth flowrate percentage F₆, the seventh flow rate percentage F₇, the eighth flowrate percentage F₈, the ninth flow rate percentage F₉, the tenth flowrate percentage F₁₀, or the eleventh flow rate percentage F₁₁ are equalto or exceed 40% of the total flow of the exhaust gas.

In various embodiments, the following configurations of the upstreamplate 300 are utilized:

20%≤F ₁≤40%  (4)

20%≤F ₂≤40%  (5)

4%≤F ₃≤20%  (6)

4%≤F ₄≤15%  (7)

1%≤F ₅≤5%  (8)

1.5%≤F ₆≤12%  (9)

1%≤F ₇≤5%  (10)

0.25%≤F ₈≤4.25%  (11)

0.5%≤F ₉≤12%  (12)

0.5%≤F ₁₀≤4.5%  (13)

0.5%≤F ₁₁≤4.5%  (14)

FIG. 4 illustrates the mixing assembly 138 with the mixing body upstreamcoupler 202, the mixing body 200, and the mixing body downstream coupler206 hidden. The mixing assembly 138 also includes a swirl plate 400. Theswirl plate 400 is disposed downstream of the upstream plate 300 and iscoupled to the upstream plate 300 relative to the injector axisC_(injector). As will be explained in more detail, the swirl plate 400interfaces with the exhaust gas after the exhaust gas has flowed throughthe upstream plate 300 and functions to cause the exhaust gas to swirl.This swirl enhances mixing of the reductant provided by the injector 120into the exhaust gas and therefore enhances the decomposition of NOR.

An upstream edge of the swirl plate 400 is located adjacent to (e.g., inconfronting relation with, next to, etc.) the upstream plate 300 suchthat the flow of the exhaust gas between the swirl plate 400 and theupstream plate 300 is prevented or minimized. In various embodiments,the swirl plate 400 includes upstream swirl plate tabs 402 thatfacilitate coupling of the swirl plate 400 to the upstream plate 300. Insome of these embodiments, the upstream plate 300 includes upstreamswirl plate openings 404 that are configured to receive the upstreamswirl plate tabs 402. In these embodiments, the upstream swirl platetabs 402 may be inserted into the upstream swirl plate openings 404 andthe upstream swirl plate tabs 402 may be bent over the upstream plate300 or welded or fastened to the upstream plate 300. In otherembodiments, the upstream plate 300 does not include the upstream swirlplate openings 404 and the upstream swirl plate tabs 402 are welded orfastened to the upstream plate 300. In still other embodiments, theswirl plate 400 does not include the upstream swirl plate tabs 402. Inthese embodiments, an upstream edge of the swirl plate 400 is welded orfastened to the upstream plate 300. In yet other embodiments, the swirlplate 400 is not coupled to the upstream plate 300.

The mixing assembly 138 also includes a downstream plate 406. Thedownstream plate 406 can be seen in FIG. 3 through the first upstreamplate opening 304, the second upstream plate opening 306, the thirdupstream plate opening 308, the fourth upstream plate opening 310, thefifth upstream plate opening 312, the sixth upstream plate opening 314,the seventh upstream plate opening 316, the eighth upstream plateopening 318, the ninth upstream plate opening 320, the tenth upstreamplate opening 322, and the eleventh upstream plate opening 324.

The downstream plate 406 includes a downstream plate edge 408 that iscoupled to the mixing body 200 relative to the injector axisC_(injector). For example, the downstream plate edge 408 may include analignment feature that is received within an alignment feature in themixing body 200 when the downstream plate edge 408 is coupled to themixing body 200 and the alignment features may be positioned based uponthe injector axis C_(injector). In various embodiments, the downstreamplate edge 408 is welded or fastened to the mixing body 200. Thedownstream plate 406 separates a portion (e.g., an upstream portion,etc.) of the mixing body 200 from the decomposition chamber downstreamportion 142 such that exhaust gas flowing out of the mixing body 200must first pass through downstream plate 406. The downstream plate 406is disposed downstream of the swirl plate 400 and is coupled to theswirl plate 400 relative to the injector axis C_(injector). As will beexplained in more detail herein, a downstream edge of the swirl plate400 is located adjacent to the downstream plate 406 such that the flowof the exhaust gas between the swirl plate 400 and the downstream plate406 is prevented or minimized.

The mixing assembly 138 also includes a first splash plate 410 and asecond splash plate 412. The first splash plate 410 and the secondsplash plate 412 are disposed downstream of the upstream plate 300 andupstream of the downstream plate 406. The first splash plate 410 and thesecond splash plate 412 are coupled to the upstream plate 300 relativeto the injector axis C_(injector) and coupled to the downstream plate406 relative to the injector axis C_(injector). As will be explained inmore detail herein, the first splash plate 410 and the second splashplate 412 are configured to interface with the reductant that is dosedinto the mixing body 200 by the injector 120 and cooperate with theswirl plate 400 to guide the exhaust gas that flows through the upstreamplate 300 so as to create a swirl.

In various embodiments, the first splash plate 410 includes an upstreamfirst splash plate tab 414 that facilitates coupling of the first splashplate 410 to the upstream plate 300. In various embodiments, theupstream plate 300 includes an upstream first splash plate opening 416that is configured to receive the upstream first splash plate tab 414.In these embodiments, the upstream first splash plate tab 414 may beinserted into the upstream first splash plate opening 416 and theupstream first splash plate tab 414 may be bent over the upstream plate300 or welded or fastened to the upstream plate 300. In otherembodiments, the upstream plate 300 does not include the upstream firstsplash plate opening 416 and the upstream first splash plate tab 414 iswelded or fastened to the upstream plate 300. In still otherembodiments, the first splash plate 410 does not include the upstreamfirst splash plate tab 414. In these embodiments, an edge of the firstsplash plate 410 is welded or fastened to the upstream plate 300.

In various embodiments, the first splash plate 410 includes downstreamfirst splash plate tabs 418 that facilitates coupling of the firstsplash plate 410 to the downstream plate 406. In various embodiments,the downstream plate 406 includes downstream first splash plate openings420 that are configured to receive the downstream first splash platetabs 418. In these embodiments, the downstream first splash plate tabs418 may be inserted into the downstream first splash plate openings 420and the downstream first splash plate tabs 418 may be bent over thedownstream plate 406 or welded or fastened to the downstream plate 406.In other embodiments, the downstream plate 406 does not include thedownstream first splash plate openings 420 and the downstream firstsplash plate tabs 418 are welded or fastened to the downstream plate406. In still other embodiments, the first splash plate 410 does notinclude the downstream first splash plate tabs 418. In theseembodiments, an edge of the first splash plate 410 is welded or fastenedto the downstream plate 406.

In various embodiments, the second splash plate 412 includes an upstreamsecond splash plate tab 422 that facilitates coupling of the secondsplash plate 412 to the upstream plate 300. In various embodiments, theupstream plate 300 includes an upstream second splash plate opening 424that is configured to receive the upstream second splash plate tab 422.In these embodiments, the upstream second splash plate tab 422 may beinserted into the upstream second splash plate opening 424 and theupstream second splash plate tab 422 may be bent over the upstream plate300 or welded or fastened to the upstream plate 300. In otherembodiments, the upstream plate 300 does not include the upstream secondsplash plate opening 424 and the upstream second splash plate tab 422 iswelded or fastened to the upstream plate 300. In still otherembodiments, the second splash plate 412 does not include the upstreamsecond splash plate tab 422. In these embodiments, an edge of the secondsplash plate 412 is welded or fastened to the upstream plate 300.

In various embodiments, the second splash plate 412 includes downstreamsecond splash plate tabs 426 that facilitates coupling of the secondsplash plate 412 to the downstream plate 406. In various embodiments,the downstream plate 406 includes downstream second splash plateopenings 428 that are configured to receive the downstream second splashplate tabs 426. In these embodiments, the downstream second splash platetabs 426 may be inserted into the downstream second splash plateopenings 428 and the downstream second splash plate tabs 426 may be bentover the downstream plate 406 or welded or fastened to the downstreamplate 406. In other embodiments, the downstream plate 406 does notinclude the downstream second splash plate openings 428 and thedownstream second splash plate tabs 426 are welded or fastened to thedownstream plate 406. In still other embodiments, the second splashplate 412 does not include the downstream second splash plate tabs 426.In these embodiments, an edge of the second splash plate 412 is weldedor fastened to the downstream plate 406.

As a result of the arrangement of the upstream plate 300, the swirlplate 400, the downstream plate 406, the first splash plate 410, and thesecond splash plate 412, the swirl plate 400, the first splash plate410, and the second splash plate 412 have identical lengths, as measuredalong the mixing body center axis C_(body) and between the upstreamplate 300 and the downstream plate 406. As such, when the mixingassembly 138 is reconfigured such that the length, as measured along themixing body center axis C_(body), is increased or decreased, the lengthsof the swirl plate 400, the first splash plate 410, and the secondsplash plate 412, as measured along the mixing body center axisC_(body), are correspondingly increased or decreased.

The first splash plate 410 comprises a plurality of first splash members430. Each of the first splash members 430 is deflected a first splashangle (past from the first splash plate 410 towards the mixing bodycenter axis C_(body). In some embodiments, the first splash angle (pastvaries amongst the first splash members 430 in order to optimize mixingof the reductant and the exhaust gas. In various embodiments, the firstsplash angle (past is between 30° and 45°, inclusive. In someembodiments, the first splash angle (past is approximately equal to 38°.Some of the exhaust gas flowing through the upstream plate 300 ispropelled against the first splash members 430 which, based on the firstsplash angle (past, cause the exhaust gas to redirected towards themixing body center axis C_(body). By including additional of the firstsplash members 430, or by increasing the area of the first splashmembers 430, the first splash plate 410 could redirect more of theexhaust gas towards the mixing body center axis C_(body). Similarly, byincluding fewer of the first splash members 430, or by decreasing thearea of the first splash members 430, the first splash plate 410 couldredirect less of the exhaust gas towards the mixing body center axisC_(body). Additionally, by increasing or decreasing the first splashangle (past, the exhaust gas can be redirected closer to the mixing bodycenter axis C_(body) or further from the mixing body center axisC_(body).

In various embodiments, the first splash plate 410 also includes aplurality of first splash openings 432. In these embodiments, each ofthe first splash members 430 is contiguous with one of the first splashopenings 432. In other embodiments, the first splash plate 410 does notinclude the first splash openings 432. In these embodiments, the firstsplash plate 410 may be corrugated and the first splash members 430 maybe formed from the corrugations of the first splash plate 410.

FIG. 5 illustrates the mixing assembly 138 with the mixing body upstreamcoupler 202, the mixing body 200, the mixing body downstream coupler206, the swirl plate 400, and the downstream plate 406 hidden. Thesecond splash plate 412 comprises a plurality of second splash members500. Each of the second splash members 500 is deflected a second splashangle φ_(second) from the second splash plate 412 towards the mixingbody center axis C_(body). In some embodiments, the second splash angleφ_(second) varies amongst the second splash members 500 in order tooptimize mixing of the reductant and the exhaust gas. In someembodiments, the second splash angle φsecond varies amongst the secondsplash members 500. In various embodiments, the second splash angleφ_(second) is between 30° and 45°, inclusive. In some embodiments, thesecond splash angle φ_(second) is approximately equal to 38°. Some ofthe exhaust gas flowing through the upstream plate 300 is propelledagainst the second splash members 500 which, based on the second splashangle φ_(second), cause the exhaust gas to redirected towards the mixingbody center axis C_(body). By including additional of the second splashmembers 500, or by increasing the area of the second splash members 500,the second splash plate 412 could redirect more of the exhaust gastowards the mixing body center axis C_(body). Similarly, by includingfewer of the second splash members 500, or by decreasing the area of thesecond splash members 500, the second splash plate 412 could redirectless of the exhaust gas towards the mixing body center axis C_(body).Additionally, by increasing or decreasing the second splash angleφ_(second), the exhaust gas can be redirected closer to the mixing bodycenter axis C_(body) or further from the mixing body center axisC_(body). In various embodiments, the second splash angle φ_(second) forall of the second splash members 500 is the same as the first splashangle (past for all of the first splash members 430.

In various embodiments, the second splash plate 412 also includes aplurality of second splash openings 502. In these embodiments, each ofthe second splash members 500 is contiguous with one of the secondsplash openings 502. In other embodiments, the second splash plate 412does not include the second splash openings 502. In these embodiments,the second splash plate 412 may be corrugated and the second splashmembers 500 may be formed from the corrugations of the second splashplate 412.

FIG. 6 illustrates the mixing assembly 138 looking from the mixing bodydownstream coupler 206 and towards the mixing body upstream coupler 202with the downstream plate 406 hidden.

The first splash plate 410 is centered on a first splash center axisC_(fs) that is parallel to the mixing body center axis C_(body). Thefirst splash center axis C_(fs) is separated from the mixing body centeraxis C_(body) by a first splash plate first offset O_(fsf) and a firstsplash plate second offset O_(fss). The first splash plate first offsetO_(fsf) is measured along a third reference axis G₃. The third referenceaxis G₃ is orthogonal to and coincident with the mixing body center axisC_(body). The first splash plate second offset O_(fss) is measured alonga fourth reference axis G₄ that is orthogonal to and coincident with themixing body center axis C_(body) and the third reference axis G₃. Asshown in FIG. 6, the first splash plate first offset O_(fsf) is largerthan the first splash plate second offset O_(fss). In variousembodiments, the first splash plate first offset O_(fsf) is between 82mm and 87 mm, inclusive and the first splash plate second offset O_(fss)is between 29 mm and 36 mm, inclusive.

The second splash plate 412 is centered on a second splash center axisC_(ss) that is parallel to the mixing body center axis C_(body). Thesecond splash center axis C_(ss) is separated from the mixing bodycenter axis C_(body) by a second splash plate first offset O_(ssf) and asecond splash plate second offset O_(sss). The second splash plate firstoffset O_(ssf) is measured along the third reference axis G₃. The secondsplash plate second offset O_(sss) is measured along the fourthreference axis G₄. As shown in FIG. 6, the second splash plate firstoffset O_(ssf) is approximately equal to the second splash plate secondoffset O_(sss). In various embodiments, the second splash plate firstoffset O_(ssf) is between 29 mm and 36 mm, inclusive and the secondsplash plate second offset O_(sss) is between 25 mm and 32 mm,inclusive.

Additionally, the first splash plate 410 has a first splash plate radiusof curvature R_(fb) and the second splash plate 412 has a second splashplate radius of curvature R_(sb). The first splash plate radius ofcurvature R_(fb) and the second splash plate radius of curvature R_(sb)are measured along a plane that is orthogonal to the mixing body centeraxis C_(body) and along which the third reference axis G₃ and the fourthreference axis G₄ extend. In various embodiments, the first splash plateradius of curvature R_(fb) is approximately equal to the second splashplate radius of curvature R_(sb). In various embodiments, the firstsplash plate radius of curvature R_(fb) is between 90 mm and 110 mm,inclusive and the second splash plate radius of curvature R_(sb) isbetween 90 mm and 110 mm, inclusive. In some embodiments, the firstsplash plate radius of curvature R_(fb) is approximately equal to 103.3mm and the second splash plate radius of curvature R_(sb) isapproximately equal to 103.3 mm.

The swirl plate 400 includes a swirl plate coupling portion 600 and aswirl plate swirl portion 602. The swirl plate coupling portion 600 hasan approximately constant slope with respect to the third reference axisG₃. In various embodiments, the swirl plate coupling portion 600 getsfurther away from the mixing body center axis C_(body) on the fourthreference axis G₄ as it gets closer to the mixing body center axisC_(body) on the third reference axis G₃.

The swirl plate swirl portion 602 is semi-circular and extends from theswirl plate coupling portion 600 along the third reference axis G₃ andpast the mixing body center axis C_(body), then extends along the fourthreference axis G₄ and past the mixing body center axis C_(body), andthen extends along the third reference axis G₃ and past the mixing bodycenter axis C_(body) again. This arrangement, as shown in FIG. 6, causesthe swirl plate swirl portion 602 to curve around the mixing body centeraxis C_(body).

The swirl plate swirl portion 602 has a swirl plate radius of curvatureR_(sp) that is measured along a plane that is orthogonal to the mixingbody center axis C_(body) and along which the third reference axis G₃and the fourth reference G₄ extend. The swirl plate radius of curvatureR_(sp) is less than the first splash plate radius of curvature R_(fb)and less than the second splash plate radius of curvature R_(sb). Insome embodiments, the swirl plate radius of curvature R_(sp) is lessthan half of the first splash plate radius of curvature R_(fb) and lessthan half of the second splash plate radius of curvature R_(sb). Invarious embodiments, the swirl plate radius of curvature R_(fb) isbetween 40 mm and 65 mm, inclusive. In some embodiments, the swirl plateradius of curvature R_(fb) is approximately equal to 54.8 mm.

The swirl plate coupling portion 600 includes a swirl plate edge 604that is located adjacent to the mixing body 200. The swirl plate edge604 is positioned such that the flow of the exhaust gas between theswirl plate edge 604 and the mixing body 200 is prevented or minimized.In some embodiments, the swirl plate edge 604 is coupled to the mixingbody 200. For example, the swirl plate edge 604 may be welded to themixing body 200.

Due to the configuration of the swirl plate edge 604, the prevention orminimization of the flow of the exhaust gas between the swirl plate 400and the upstream plate 300, and the prevention or minimization of theflow of the exhaust gas between the swirl plate 400 and the downstreamplate 406, the swirl plate 400 defines a swirl collection region 606 anda swirl concentration region 608. The swirl collection region 606 andthe swirl concentration region 608 extend between the upstream plate 300and the downstream plate 406 and are separated by the swirl plate 400and a swirl region boundary 610. The swirl region boundary 610 extendsin a straight plane from a leading edge 612 of the swirl plate swirlportion 602 to the mixing body 200 such that each of the first upstreamplate opening 304, the second upstream plate opening 306, the thirdupstream plate opening 308, the fourth upstream plate opening 310, thefifth upstream plate opening 312, the sixth upstream plate opening 314,the seventh upstream plate opening 316, the eighth upstream plateopening 318, the ninth upstream plate opening 320, the tenth upstreamplate opening 322, and the eleventh upstream plate opening 324 iscontained within the swirl collection region 606 and the volume of theswirl collection region 606 is minimized. As shown in FIG. 6, the swirlregion boundary 610 is contiguous with an edge of the eleventh upstreamplate opening 324.

The reductant is dosed into the swirl collection region 606 by theinjector 120 and along the injector center axis C_(injector). As thereductant is propelled into the swirl collection region 606, thereductant is carried towards the first splash plate 410, the secondsplash plate 412, and the mixing body 200. Proximate the injector 120,the reductant is surrounded by the exhaust gas so as to cause propulsionof the reductant along with the exhaust gas towards the swirlconcentration region 608.

In various embodiments, the mixing assembly 138 is configured such thatthe injector center axis C_(injector) extends between the third upstreamplate opening 308 and the fourth upstream plate opening 310 (e.g., thethird upstream plate opening 308 does not extend over the injectorcenter axis C_(injector) and the fourth upstream plate opening 310 doesnot extend over the injector center axis C_(injector), etc.). In thisway, the exhaust gas flows around the reductant being dosed by theinjector 120, thereby avoiding propelling the reductant against thedownstream plate 406 and instead create a barrier mitigating theformation (e.g., impingement, etc.) or accumulation of reductantdeposits on the downstream plate 406. Furthermore, by causing theexhaust gas to flow against the downstream plate 406, the third upstreamplate opening 308 and the fourth upstream plate opening 310 function towarm the downstream plate 406 and maintain a temperature of thedownstream plate 406 above a threshold. When the temperature of thedownstream plate 406 is above the threshold, formation or accumulationof reductant deposits on the downstream plate 406 is further mitigated(e.g., due to evaporation of the reductant upon contacting thedownstream plate 406, etc.).

The upstream plate 300 is configured to create a shear flow on the swirlplate 400, the first splash plate 410, the second splash plate 412, andthe mixing body 200 so as to prevent or mitigate the formation oraccumulation of reductant deposits on the first splash plate 410. Inthis way, the mixing assembly 138 is capable of desirably mixing thereductant and the exhaust gas for a longer period of time (e.g., betweenservicing or cleaning of the mixing assembly 138, etc.) than would bepossible if the shear flow was not created by the upstream plate 300.

The first upstream plate opening 304 is disposed proximate the swirlplate 400. As the exhaust gas flows through the first upstream plateopening 304, some of the exhaust gas flows across the swirl plate 400and creates a shear flow on the swirl plate 400. This shear flow propelsthe reductant away from or off of the swirl plate 400. In this way, thefirst upstream plate opening 304 may function to mitigate the formationor accumulation of reductant deposits on the swirl plate 400.

The first splash plate 410 is coupled to the upstream plate 300 and thedownstream plate 406 so as to extend over the second upstream plateopening 306. As the exhaust gas flows through the second upstream plateopening 306 and into the swirl collection region 606, some of theexhaust gas flows across the first splash plate 410 and creates a shearflow on the first splash plate 410. This shear flow propels thereductant away from or off of the first splash plate 410. In this way,the second upstream plate opening 306 may function to mitigate theformation or accumulation of reductant deposits on the first splashplate 410.

The fifth upstream plate opening 312 is disposed proximate the firstsplash plate 410 and the second splash plate 412. As the exhaust gasflows through the fifth upstream plate opening 312, some of the exhaustgas flows across the first splash plate 410 and creates a shear flow onthe first splash plate 410. This shear flow propels the reductant awayfrom or off of the first splash plate 410. Additionally, some of theexhaust flows across the second splash plate 412 and creates a shearflow on the second splash plate 412. This shear flow propels thereductant away from or off of the second splash plate 412. In this way,the fifth upstream plate opening 312 may function to mitigate theformation or accumulation of reductant deposits on the first splashplate 410 and the second splash plate 412.

The second splash plate 412 is coupled to the upstream plate 300 and thedownstream plate 406 so as to extend over the first upstream plateopening 304. As the exhaust gas flows through the first upstream plateopening 304 and into the swirl collection region 606, some of theexhaust gas flows across the second splash plate 412 and creates a shearflow on the second splash plate 412. This shear flow propels thereductant away from or off of the second splash plate 412. In this way,the first upstream plate opening 304 may function to mitigate theformation or accumulation of reductant deposits on the second splashplate 412.

The sixth upstream plate opening 314 and the seventh upstream plateopening 316 are disposed proximate the swirl plate 400 and the secondsplash plate 412. As the exhaust gas flows through the sixth upstreamplate opening 314 and the seventh upstream plate opening 316, some ofthe exhaust gas flows across the swirl plate 400 and creates a shearflow on the swirl plate 400. This shear flow propels the reductant awayfrom or off of the swirl plate 400. Additionally, some of the exhaustflows across the second splash plate 412 and creates a shear flow on thesecond splash plate 412. This shear flow propels the reductant away fromor off of the second splash plate 412. In this way, the sixth upstreamplate opening 314 and the seventh upstream plate opening 316 mayfunction to mitigate the formation or accumulation of reductant depositson the swirl plate 400 and the second splash plate 412.

The eighth upstream plate opening 318, the ninth upstream plate opening320, the tenth upstream plate opening 322, and the eleventh upstreamplate opening 324 are contiguous with the mixing body 200. As theexhaust gas flows through the eighth upstream plate opening 318, theninth upstream plate opening 320, the tenth upstream plate opening 322,and the eleventh upstream plate opening 324 and into the swirlcollection region 606, some of the exhaust gas flows across the mixingbody 200 and creates a shear flow on the mixing body 200. This shearflow propels the reductant away from or off of the mixing body 200proximate the eighth upstream plate opening 318, the ninth upstreamplate opening 320, the tenth upstream plate opening 322, and theeleventh upstream plate opening 324. In this way, the eighth upstreamplate opening 318, the ninth upstream plate opening 320, the tenthupstream plate opening 322, and the eleventh upstream plate opening 324may function to mitigate the formation or accumulation of reductantdeposits on the mixing body 200.

The total area of the eighth upstream plate opening 318, the ninthupstream plate opening 320, the tenth upstream plate opening 322, andthe eleventh upstream plate opening 324 is relatively small compared tothe area of, for example, the first upstream plate opening 304 or thearea of the second upstream plate opening 306, because, as describedabove, the mixing assembly 138 is configured to mitigate the amount ofreductant that contacts the mixing body 200. Without the variousfeatures described above, such as the swirl plate 400, the first splashplate 410, and the second splash plate 412 or the location of the firstupstream plate opening 304, the second upstream plate opening 306, thethird upstream plate opening 308, the fourth upstream plate opening 310,the fifth upstream plate opening 312, the sixth upstream plate opening314, or the seventh upstream plate opening 316, the total area of theeighth upstream plate opening 318, the ninth upstream plate opening 320,the tenth upstream plate opening 322, and the eleventh upstream plateopening 324 may have to be increased in order to mitigate the formationor accumulation of deposits on the mixing body 200.

FIG. 7 illustrates the mixing assembly 138 looking from the mixing bodydownstream coupler 206 and towards the mixing body upstream coupler 202.As shown in FIG. 7, the downstream plate 406 includes a downstream plateopening 700 and the downstream plate 406 is coupled to the mixing body200 across or within a downstream mixing body opening 701 of the mixingbody 200. The downstream plate 406 does not include any opening otherthan the downstream plate opening 700 and the exhaust gas is only ableto pass through the downstream plate 406 via the downstream plateopening 700.

The downstream plate opening 700 is positioned around the swirlconcentration region 608. After the exhaust gas is provided into theswirl concentration region 608, the velocity of the exhaust gasincreases and the exhaust gas flows through the downstream plate opening700 with the swirl created in the swirl collection region 606 and theswirl concentration region 608.

A downstream swirl plate edge 702 of the swirl plate 400 extends into orthrough the downstream plate opening 700 and is positioned adjacent thedownstream plate 406 such that the flow of the exhaust gas between theswirl plate 400 and the downstream plate 406 is prevented or minimized.In some embodiments, the downstream swirl plate edge 702 is bent overthe downstream plate 406 or welded or fastened to the downstream plate406. In other embodiments, the downstream swirl plate edge 702 is sealedheld against the downstream plate 406 via tensile forces within theswirl plate 400 that are created by bending the swirl plate 400.

Due to the configuration of the mixing body 200, upstream plate 300, theswirl plate 400, the first splash plate 410, the second splash plate412, and the downstream plate 406, the mixing assembly 138 operates witha desirable pressure drop (e.g., a pressure drop that is below athreshold associated with per performance for an exhaust aftertreatmentsystem, etc.) when comparing a pressure upstream of the mixing assembly138 and a pressure downstream of the mixing assembly 138. Additionally,the configuration of the mixing body 200, upstream plate 300, the swirlplate 400, the first splash plate 410, the second splash plate 412, andthe downstream plate 406 provides a desirable flow distribution index(FDI) at an upstream face of the SCR catalyst 110.

FIGS. 8-10 illustrate velocity magnitudes of the exhaust gas flowingthrough the mixing assembly 138, according to various embodiments.Viewed in sequence, FIG. 8, FIG. 9, and FIG. 10, illustrate the velocitymagnitudes of the exhaust gas from a first location just downstream ofthe upstream plate 300 (FIG. 8) to a third location just upstream of thedownstream plate 406 (FIG. 10), and a second location therebetween (FIG.9).

As shown in FIGS. 8-10, a flow of the exhaust gas enters the swirlcollection region 606 through the upstream plate 300. This createslocalized regions with relatively high velocity magnitudes in the swirlcollection region 606 proximate the first upstream plate opening 304,the second upstream plate opening 306, the third upstream plate opening308, the fourth upstream plate opening 310, the fifth upstream plateopening 312, the sixth upstream plate opening 314, the seventh upstreamplate opening 316, the eighth upstream plate opening 318, the ninthupstream plate opening 320, the tenth upstream plate opening 322, andthe eleventh upstream plate opening 324. These localized regions aremost prominent near the upstream plate (FIG. 8) and least prominentfarthest away from the upstream plate (FIG. 10).

The mixing body 200, the swirl plate 400, the first splash plate 410,and the second splash plate 412 cooperate to redirect the exhaust gasand cause the exhaust gas to be spun out of the swirl collection region606 towards the swirl concentration region 608. As the exhaust gasapproaches the swirl region boundary 610, the velocity of the exhaustgas gradually increases. Once in the swirl concentration region 608, thevelocity of the exhaust gas rapidly increases as the exhaust gas swirlsalong the mixing body 200, along the swirl plate 400, and out of thedownstream plate opening 700. Through this swirl, the reductant providedby the injector 120 is effectively mixed with the exhaust gas.

By varying the first splash plate first offset O_(fsf), the first splashplate second offset O_(fss), the second splash plate first offsetO_(ssf), the second splash plate second offset O_(sss), the first splashplate radius of curvature R_(fb), and the second splash plate radius ofcurvature R_(sb), the first splash plate 410 and the second splash plate412 can be positioned within the mixing body 200 such that the swirlcreated by the swirl plate 400 is enhanced (e.g., tightened,concentrated, etc.).

When an application for the mixing assembly 138 is determined, a modelof the mixing assembly 138 can be uploaded into a computational fluiddynamics (CFD) solution such as ANSYS Fluent or SOLIDWORKS® FlowSimulation and variables such as the number of first splash members 430,the number of the first splash openings 432, the first splash angleφ_(first), the first splash plate first offset O_(fsf), the first splashplate second offset O_(fss), the second splash plate first offsetO_(ssf), the second splash plate second offset O_(sss), the first splashplate radius of curvature R_(fb), and the second splash plate radius ofcurvature R_(sb) can be optimized to provide a target swirl of theexhaust gas between the upstream plate 300 and the downstream plate 406which is associated with a target dispersal (e.g., uniformity index,etc.) of the reductant in the exhaust gas.

FIGS. 11 and 12 show temperature gradients within the mixing assembly138, according to various embodiments. FIG. 11 illustrates thetemperature gradients within the mixing assembly 138 prior to theinjector 120 dosing the reductant into the mixing assembly 138 and FIG.12 illustrates the temperature gradients within the mixing assembly 138after the injector 120 has dosed the reductant into the mixing assembly138.

FIG. 12 shows localized areas that are of relatively lower temperature.These areas are locations where the reductant is most prevalent. Withoutthe configuration of the mixing assembly 138 described herein, reductantdeposits may form or accumulate in such areas. However, the mixingassembly 138 is configured such that locations where reductant isprevalent are both heated (e.g., by the eighth upstream plate opening318, the ninth upstream plate opening 320, the tenth upstream plateopening 322, and the eleventh upstream plate opening 324, etc.) andprovided with a shear flow. In these ways, the formation or accumulationof reductant deposits within the mixing assembly 138 is mitigated.

It is understood that additional injector mounts 208 could be includedin the mixing assembly 138 such that additional injectors 120 could beused with the mixing assembly 138.

IV. Construction of Example Embodiments

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of what may beclaimed but rather as descriptions of features specific to particularimplementations. Certain features described in this specification in thecontext of separate implementations can also be implemented incombination in a single implementation. Conversely, various featuresdescribed in the context of a single implementation can also beimplemented in multiple implementations separately or in any suitablesubcombination. Moreover, although features may be described as actingin certain combinations and even initially claimed as such, one or morefeatures from a claimed combination can, in some cases, be excised fromthe combination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

As utilized herein, the terms “substantially,” generally,”“approximately,” and similar terms are intended to have a broad meaningin harmony with the common and accepted usage by those of ordinary skillin the art to which the subject matter of this disclosure pertains. Itshould be understood by those of skill in the art who review thisdisclosure that these terms are intended to allow a description ofcertain features described and claimed without restricting the scope ofthese features to the precise numerical ranges provided. Accordingly,these terms should be interpreted as indicating that insubstantial orinconsequential modifications or alterations of the subject matterdescribed and claimed are considered to be within the scope of theinvention as recited in the appended claims.

The terms “coupled” and the like, as used herein, mean the joining oftwo components directly or indirectly to one another. Such joining maybe stationary (e.g., permanent) or moveable (e.g., removable orreleasable). Such joining may be achieved with the two components or thetwo components and any additional intermediate components beingintegrally formed as a single unitary body with one another, with thetwo components, or with the two components and any additionalintermediate components being attached to one another.

The terms “fluidly coupled to” and the like, as used herein, mean thetwo components or objects have a pathway formed between the twocomponents or objects in which a fluid, such as air, exhaust gas, liquidreductant, gaseous reductant, aqueous reductant, gaseous ammonia, etc.,may flow, either with or without intervening components or objects.Examples of fluid couplings or configurations for enabling fluidcommunication may include piping, channels, or any other suitablecomponents for enabling the flow of a fluid from one component or objectto another.

It is important to note that the construction and arrangement of thesystem shown in the various example implementations is illustrative onlyand not restrictive in character. All changes and modifications thatcome within the spirit and/or scope of the described implementations aredesired to be protected. It should be understood that some features maynot be necessary, and implementations lacking the various features maybe contemplated as within the scope of the application, the scope beingdefined by the claims that follow. When the language “a portion” isused, the item can include a portion and/or the entire item unlessspecifically stated to the contrary.

Also, the term “or” is used in its inclusive sense (and not in itsexclusive sense) so that when used, for example, to connect a list ofelements, the term “or” means one, some, or all of the elements in thelist. Conjunctive language such as the phrase “at least one of X, Y, andZ,” unless specifically stated otherwise, is otherwise understood withthe context as used in general to convey that an item, term, etc. may beeither X, Y, Z, X and Y, X and Z, Y and Z, or X, Y, and Z (i.e., anycombination of X, Y, and Z). Thus, such conjunctive language is notgenerally intended to imply that certain embodiments require at leastone of X, at least one of Y, and at least one of Z to each be present,unless otherwise indicated.

Additionally, the use of ranges of values (e.g., W to P, etc.) hereinare inclusive of their maximum values and minimum values (e.g., W to Pincludes W and includes P, etc.), unless otherwise indicated.Furthermore, a range of values (e.g., W to P, etc.) does not necessarilyrequire the inclusion of intermediate values within the range of values(e.g., W to P can include only W and P, etc.), unless otherwiseindicated.

What is claimed is:
 1. A mixing assembly for an exhaust aftertreatmentsystem, the mixing assembly comprising: a mixing body comprising anupstream mixing body opening and a downstream mixing body opening, theupstream mixing body opening configured to receive exhaust gas; anupstream plate coupled to the mixing body, the upstream plate comprisinga plurality of upstream plate openings, each of the plurality ofupstream plate openings configured to receive a flow percentage that isless than 50% of a total flow of the exhaust gas; a downstream platecoupled to the mixing body downstream from the upstream plate in adirection of exhaust gas flow, the downstream plate comprising adownstream plate opening; and a swirl plate positioned between theupstream plate and the downstream plate and defining a swirl collectionregion and a swirl concentration region contiguous with the swirlcollection region, the swirl collection region positioned over theplurality of upstream plate openings and the swirl collection regionpositioned over the downstream plate opening.
 2. The mixing assembly ofclaim 1, wherein the plurality of upstream plate openings comprises afirst upstream plate opening that is configured to receive a first flowpercentage that is less than 40% of the total flow of the exhaust gas.3. The mixing assembly of claim 2, wherein the plurality of upstreamplate openings further comprises a second upstream plate opening that isconfigured to receive a second flow percentage that is less than 10% ofthe total flow of the exhaust gas.
 4. The mixing assembly of claim 1,further comprising a splash plate positioned between the upstream plateand the downstream plate and located in the swirl collection region, thesplash plate comprising a plurality of splash plate openings.
 5. Themixing assembly of claim 4, further comprising an injector mount coupledto the mixing body and configured to be coupled to an injector such thatan injector center axis of the injector extends into the swirlcollection region; wherein the splash plate is coupled to the upstreamplate and the downstream plate.
 6. The mixing assembly of claim 5,wherein the injector center axis intersects the splash plate.
 7. Themixing assembly of claim 1, wherein: the plurality of upstream plateopenings comprises: a first upstream plate opening that is configured toreceive a first flow percentage that is between 20% and 40%, inclusiveof the total flow of the exhaust gas; and a second upstream plateopening that is configured to receive a second flow percentage that isbetween 20% and 40%, inclusive of the total flow of the exhaust gas; andthe second flow percentage is less than the first flow percentage. 8.The mixing assembly of claim 7, wherein: the plurality of upstream plateopenings further comprises: a third upstream plate opening that isconfigured to receive a third flow percentage that is between 4% and20%, inclusive of the total flow of the exhaust gas; and a fourthupstream plate opening that is configured to receive a fourth flowpercentage that is between 4% and 15%, inclusive of the total flow ofthe exhaust gas; the third flow percentage is less than the second flowpercentage; and the fourth flow percentage is less than the third flowpercentage.
 9. The mixing assembly of claim 8, wherein: the plurality ofupstream plate openings further comprises a fifth upstream plate openingthat is configured to receive a fifth flow percentage that is between 1%and 5%, inclusive, of the total flow of the exhaust gas; and the fifthflow percentage is less than the fourth flow percentage.
 10. The mixingassembly of claim 1, further comprising an injector mount coupled to themixing body and configured to be coupled to an injector such that aninjector center axis of the injector extends into the swirl collectionregion; wherein the injector center axis does not intersect the swirlplate.
 11. The mixing assembly of claim 10, wherein: the mixing body iscentered on a mixing body center axis; and the injector mount isconfigured such that the injector center axis is orthogonal to themixing body center axis.
 12. A mixing assembly comprising: a mixing bodycomprising an upstream mixing body opening and a downstream mixing bodyopening, the upstream mixing body opening configured to receive exhaustgas; an upstream plate coupled to the mixing body, the upstream platecomprising a first upstream plate opening that is configured to receivea first flow percentage that is between 20% and 40%, inclusive of atotal flow of the exhaust gas; and an injector mount coupled to themixing body and configured to be coupled to an injector, the injectormount defined by an injector center axis that does not extend across thefirst upstream plate opening.
 13. The mixing assembly of claim 12,wherein: the upstream plate further comprises a second upstream plateopening that is configured to receive a second flow percentage that isbetween 0.28% and 12%, inclusive of the total flow of the exhaust gas;the second upstream plate opening is formed between the mixing body andthe upstream plate; and the injector center axis extends between thefirst upstream plate opening and the second upstream plate opening. 14.The mixing assembly of claim 12, further comprising: a downstream platecoupled to the mixing body downstream from the upstream plate in adirection of exhaust gas flow, the downstream plate comprising adownstream plate opening; and a swirl plate positioned between theupstream plate and the downstream plate and defining a swirl collectionregion and a swirl concentration region contiguous with the swirlcollection region, the swirl collection region extending across thefirst upstream plate opening and the swirl collection region extendingacross the downstream plate opening.
 15. The mixing assembly of claim14, wherein: the mixing body is centered on a mixing body center axis;and the swirl plate extends between the mixing body center axis and thefirst upstream plate opening.
 16. The mixing assembly of claim 15,further comprising a splash plate coupled to the upstream plate andlocated in the swirl collection region, the splash plate comprising: aplurality of splash members; and a plurality of splash plate openings,each of the plurality of splash plate openings contiguous with one ofthe plurality of splash members; wherein the swirl plate extends betweenthe mixing body center axis and the splash plate.
 17. A mixing assemblycomprising: a mixing body comprising an upstream mixing body opening anda downstream mixing body opening, the upstream mixing body openingconfigured to receive exhaust gas; an upstream plate coupled to themixing body, the upstream plate comprising an upstream plate openingthat is configured to receive a first flow percentage that is between20% and 40%, inclusive of a total flow of the exhaust gas; and a swirlplate coupled to the upstream plate and defining a swirl collectionregion and a swirl concentration region contiguous with the swirlcollection region, the swirl collection region extending across theupstream plate opening and the swirl collection region separated fromthe upstream plate opening by the swirl plate.
 18. The mixing assemblyof claim 17, further comprising: a first splash plate coupled to theupstream plate and located in the swirl collection region, the firstsplash plate comprising: a plurality of first splash members; and aplurality of first splash plate openings, each of the plurality of firstsplash plate openings contiguous with one of the plurality of firstsplash members; and a second splash plate coupled to the upstream plateand located in the swirl collection region, the second splash platecomprising: a plurality of second splash members; and a plurality ofsecond splash plate openings, each of the plurality of second splashplate openings contiguous with one of the plurality of second splashmembers.
 19. The mixing assembly of claim 18, wherein: the mixing bodyis centered on a mixing body center axis; the swirl plate extendsbetween the mixing body center axis and the first splash plate; and theswirl plate extends between the mixing body center axis and the secondsplash plate.
 20. The mixing assembly of claim 19, wherein: the upstreamplate is disposed along a plane; and the mixing body center axis isorthogonal to the plane.